Containers for storing and transporting produce have long been used in the fruit and vegetable marketing industry. The primary requirements of such containers are that they be strong and durable, inexpensive to manufacture and use, and of suitable dimensions to hold the particular items being stored or transported.
Cartons with trays or comprtments to hold fragile items in place during transit are not uncommon. Inserts and liners to protect delicate foodstuffs from rough handlers or the natural elements are often included in packaging designs.
The universally accepted choice among materials for constructing these cartons has been corrugated fiberboard. Because of its light weight, fiberboard does not add unduly to the total weight of the shipment when compared with wood cartons, therefore helping to keep transportation costs at a minimum. Though fiberboard is relatively weak and susceptible to moisture and deterioration, the fact that it is an inexpensive material to manufacture cartons from makes those cartons readily disposable.
One drawback inherent to cardboard and fiberboard containers--not merely cartons to transport produce, but any container folded from cardboard or fiberboard which is fastened together along overlapping or abutting panels--is their tendency to weaken and tear as progressively heavier loads are placed inside them. This is particularly true if the cartons have base supporting panels which overlap and are fastened together. The predominant trend has been toward containers with one-piece base and sidewall construction which eliminate any fastened joints between at least two of the side walls of the container and the base support panel, thus forming a unified U-shaped side wall and base panel configuration.
One limitation to current designs is that, once such a container is folded and fastened, it cannot later be unfastened and unfolded or laid flat for storage without destroying the container. A second limitation has been the need to use some external means to restrain a stack of cartons while in transit, such as ropes, netting, webbing belts, or tapes. Cardboard has a relatively smooth surface with a low coefficient of friction, and while handles or handgrips may be used to allow people to hold the cartons while carrying them, some device is necessary to prevent the top cartons from sliding off a stack when the cartons are being shipped.
In addition to designing a container which is inexpensive yet provides reasonable measures of durability and protection for the produce, one goal has also been to find methods to keep perishable goods as fresh as possible with a minimum of spoilage. Consequently, corrugated fiberboard containers with perforations and ventilation holes have been used, and transportation vehicles equipped with refrigeration are common.
Periodically misting or humidifying fruits and vegetables has been shown to be beneficial for preserving the freshness, flavor, texture, and color of many such items. Numerous United States patents have disclosed systems for misting or humidifying produce in display cases at the point of sale. Such systems would be impractical to use in transport vehicles, however, because the misting would severely delapidate standard cardboard and fiberboard cartons, and the time and expense involved in removing the produce from cartons to place them on drainage shelves within the vehicle and subsequently repacking them at the destination would destroy any advantage obtained by using the misting system.
One object of this invention is to fashion a folded container which may be quickly and easily folded flat, yet which presents a means for connecting overlapping base support panels in such a manner that they become stronger as the weight of the load in the container is increased.
Another object of this invention is to construct a stackable container with these stated advantages which interlocks with like-designed cartons to prevent a stack of cartons from shifting in transit.
An additional object of this invention is to present a design for a produce storage and transportation container which will maintain its strength and integrity despite being exposed to moisture from the container's cargo, the natural elements, or an artificial source of humidity or misted water.
Yet another object of this invention is to present a method for keeping fruits and vegetables fresh during transit by misting cool water directly on the produce while it remains in the cartons within the transport vehicle, permitting adequate drainage of excess water and not deteriorating the cartons.
An additional object of this invention is to accomplish the above advantages using a container which is relatively inexpensive and easy to manufacture, yet will be more durable and versatile than existing containers.